Marble shooter



Patented Feb. 7, 1950 uiten sTATes PATENT.

My invention relates to amusement devices and particularly to a game of the so-called pin-ball type. Specically, the invention pertains to spring-actuated ball-propelling devices for use in pin-ball and like games of skill and chance.

Pin-ball and similar games commonly employ a manually controlled actuating plunger for propelling balls along the playing area or pin-board, the inner end of the plunger being disposed in a guideway into which balls are advanced and from which the balls are driven by the plunger. The plunger is slidable in a bearing member on the casing of the game and is propelled rapidly in the guideway under the action of a spring compressed between the bearing member and the striker head of the plunger. The propelling force of the plunger and, consequently, the travel of the ball are dependent entirely upon the degree of compression of the spring. It has been determined that the inherent force per unit of length of the spring is relatively small during the initial contraction in the length of the spring but during the contraction of the spring to a length smaller than substantially one-half its original length the force or energy increases at a greater ratio. Since equal units of contraction of the spring produce unequal degrees of inherent force or stored up energy, it will be apparent that the propelling force of the spring is extremely difficult to estimate and control and consequently the ball is apt to over-drive or under-drive its objective on the pin-board.

It has also been found that conventional ballpropelling springs are usually compressed to their elastic limit when fully contracted and this results in gradual weakening and ultimate breaking of the springs. Because the resiliency of the spring is soon reduced when subjected to repeated contractions, it has heretofore been found necessary to provide adjusting means for Aperiodically shortening the length of the spring to maintain its inherent force or energy substantially constant. It will be apparent that the amount of permissible adjustment is limited and consequently the resiliency of the spring will eventually be reduced to a value wherein the spring is no longer useful and must be replaced by a spring possessing the necessary characteristics. It is thus seen that the ball-propelling device of the game requires considerable servicing to maintain it in operative condition. In order to overcome this deficiency, an attempt has been made to utilize a spring having an inherent strength far in excess of that required to propel the ball but when such a spring is employed, accurate shooting of the` ball is impossible.

It is the primary object of my invention to provide a ball-propelling device for use in pin-ball and.` like games, said device having means for regulatingV the contraction of the plunger-actuating spring whereby to enable a player to control the travel of the ball along the playing board with precision.

Another object is to provide a ball-propelling device having means for limiting the contraction of the propelling spring to that portion of' its possible contraction wherein the ratio between the inherent force of the spring and its length increases at a substantially uniform rate to enable a player to estimate the projection of the ball more accurately and avoid over-driving or under-driving a selected objective on the pinboard.

Another object is to provide a device of the character referred to which is simple in construction, being composed of a minimum number of parts adapted for economical manufacture and assembly.

A further object is to provide a device of the type indicated which requires very little servicing and one which may be readily substituted for devices of prior types now in use without changing the structure of the game.

Further objects of my invention will appear from the following specification and the drawing, which is intended for the purpose of illustration only, and in which:

Fig. 1 is a plan view of a portion of the casing of a pin-ball game, illustrating my improved ballpropelling device as applied to use therewith;

Fig. 2 is a longitudinal sectional View through v the device, taken on line 2 2 of Fig. 1, and showing the ball-propelling plunger in extended position; and

Fig. 3 is a View similar to Fig. 2 showing the plunger in fully retracted position.

My improved ball-propelling device comprises, in general, a bearing member adapted for attachment to the side of the casing of a pin-ball rgame, said bearing member being provided with a bore and a tubularV extension axially aligned with said bore, a tubular plunger slidable in the tubular extension and provided with a striker head at its outer end, a stem connected to said striker head and extending through the bore of the bearing member, an operating knob carried on the projecting end of the stem, anda compressible spring surrounding the stem between the striker head and the bearing member and operative to project the plunger into the ball guideway of the game casing to strike and propel la ball from said guideway onto the pin-board of the game.

Sliding movement of the ball-propelling plunger to operative or extended position is limited by the engagement of the operating knob with the side of the bearing member While movement of the plunger to retracted position is limited byengagement of the striker head with thefend of the tubular extension so that maximum contraction of the propelling spring is limited to substantially one-half of the extended length of the spring.

Referring to the drawing in detail, the improved ball-propelling device 5 is shownasapplied to use with a Vpin-ball game comprising a box-dike casing having a bottom wall 'l and side walls El and 9. A partition member I cooperates with the wall Si in dening a guideway Il into which playing balls l2 are advanced and frornwhich they are propelled individually onto the Lpinboard i3 by the present device.

My device 5 comprises, essentially, va bea-ring member i5 of substantially frusto-conical shape and having a cylindrical boss or projection I6 at .its outer end and ailat face il at its inner end. ALIh'e :bearing vmember "has a bore i8, a i`counter- 'bore i9 and a y'threaded counterbore 123. The bearing member l5 is further provided with tapped holes '2l inits inner end"forreceivingat ta'ching screws i22 `which pass througlfl Vholes m the sidewall 8 to secure the bearing-member'in `vplace. .Screwed into thetappe'd counterbore j2i3 is one end of a *tubular Vmember por 's'leeve' which, in effect, constitutesan'axial extensionof the bearing member'l 5.

.Adapted to Vslide in .the extension. sleeve L25 'is a 'tubular plunger member El. The projecting end .of thememberl'l isinternally threaded to receive .one end .of .a connector Yelement 28 which fis screwed .therento Theeotherend .of lthe .con- .necton elementi 8 lproj ectsaxially 'fromthe plunger member 2l for receiving a strikerfhea'd `30 ,whichissorewed thereon. The head-may be .providedA-witha rubber ,pad il adapted to strike `Aajplaying ballwhen the plungergmemberll.isslid to ,operative position `.in ythe ,manner `to .be .eX- plained hereinafter.

. Screwed into atappedholeSSntheLinnerE-end Aof Athe connector Aelement .28 is one =endcof a.rod- .like ystem 34 whichextendsaxially through,the

tubular plunger member 2l and extension. Zvand .which lis slidable rin the bore I8 ,of the bearing member l5. The `stem .-34 projects outwardly beyond .the projection 1,6 .to receive an .operating :knob whichfisfsecured thereto byra vpinl. rubber A.cushion or buffer 'ring ,33 .is disposed on the stemfil between .the knob.--35and.the endof the projection l5.

-Surrounding:thestem @mand entirelyenclosed by the bearing :member l5, sleeve Zrrandplunger member 12 i 'is a ',compressionrspringllhaving ione fof its ends abutting the rend .ofthe counterbore 9 and 'rts :other end engaging dalle inner :gend :of

the .connector element iZ. .The :spring :Ml .iis

v:normally compressed to i afslight ."degre'e 'when the parts :of the device assume the position .illustrated lin "Fig .2 of the .drawing :but Iurther :ont- I'ward sliding :movement of .the Aplunger member r=2fis'prevented by the engagement of'tl'i'eoperat-A ting knob and Vitsbu'ierring'lll withtheen'd "cftheboss or projection I 6.

`lvlyimp'roved ball-propelling device is operated "lnithe followingmanner:

AAssuming that-theparts of the deviceare in the position showni'in FigsjllandZ-'arrdlthat agplaying y'ball i2 is-restingfagainst the pad 3l of" the striker l'head -BS within the 'gui'deway Il, "to propel 'the ball romthe guideway'theplayer or contestant grasps the'knobiy and draws the plunger member 21 4intothe tubular extension'. The Aguideway EI is usually inclined slightly 4so tlratasthe` plungfervrmember 27 lis retracted Yinto the extension 25 lthe 1ball i2 -will tend to Aroll 'down the incline, #movement of the ball in 4this direction -being limited by a pair of upstanding pins 42 in the guideway.

As the plunger member 21 is retracted into the extensionrsleeve 2b, the Yspring Ml. is compressed 1`and thus 'its propelling force or energy is increased, the magnitude of the force being dependent upon the degree of contraction of the spring. It will be observed by reference t@ Fig. 3 that the Vinward-i-sliding movement of the plunger memizThrough itliis novel and ingenious arrangement vof parts, *only rvone-half of the possible contrac- "-tiono'fthe spring 'iis utilized and because the strength l'of the spring increases -in 'almost 'direct proportion to the'reducti'c'n in length ofthe spring during 'this portion of fits contraction, lit fis f-apparent that azplayer may readily estimate 'and y'regulate the Astrength of `th`e spring to f controlits expansive force -or energy.

-Afterthe-spring 4 has'been compressedto' the desired degree, fthe knob is released and-the `plunger1meniber :21' is thus "projected "'fronrthe `#sleeve 25at"arelativelyfast rate under the-'ex- 'Apanrsive forcefof the spring'to .eject theball l2 "romthe gudevvay -H'an'd 'propelt it'ontd the pin- Elboard i3. 'If'the ball '.1'2 over-drivesJorunder- 'drives a selected fobjective on the.p'inlboard, the inaccuracymay *be f correctedwhen the nextball is divenfby retractingthe plunger Imember12'! fto @a greater/'or lesser extent 'to 'compress the spring allft'oithe required degree. -.Longitudinally-spaced :graduations fzm'ay Ybe provi'dedfwithin thenguideway lf I #said graduations being adapted to -reg- -ister Iwith the 'end -of 'the striker head yto aid infdeterininingthe degree 'of compression vcfthe fspring y'fithwhen ythe fpiungerlmernberiiszretracted. 'itwillbefobserved from theforegoingthat invention provides an iimproved ball-'umpelling :device 'ladapted 7particularly "for use in pin-ball ;an`d=sinilar games dfskillandfchance. y.Asiaparfticular feature of improvement, the invention provides a ball-propelling 'device having 'means for accuratelyicontrolling the 'propelling force of the spring-actuated 'plunger whereby to enable Ltheplayer-or 'contestant :to regulate the travel Aof :the V,playing Vball with greater precision. :Specically the i invention provides vmeans `for ilimit- .zing the contraction :of vthe propelling spring 'to sbs'tan'tiallyionelhalf 'of its possible contraction jarrdsince th'e A"strength rif vuthe spring increas'es'fin almost:directgproportion tcitsrreductionk in length vduring this portion :nf Vvits 'contraction a player ',mayreadily :estimate and regulate the strength dlrthespringto control :its .expansiveorce YB y compressing .the spring to ioniyfaportion of its elastic Llimit, the v`spring .is not hiat'erially `weak- 'ened `duringcontinuous use and 'thus will retain its linlfierentresiliency over fa 'long Aperiod 'of time 'without breaking. 'It'is'apparent'therefore that `a ball-'propelling device incorporatingjthe fea- 'tures "of "improvement herein disclosed ishiglily efcient in; performing l"its intended function and requires "Verylittle servicing. The improve'd 'dev"vice is simple .in construction andirnayibe manu- .facture'd-'a't va 'comparatively low cost. Moreover, the device may be supplied as'areplacement for similar devices now in use an'dmaybeincorporatedin Vvthe "game without altering lthe structure t'hereo @While I have fshown v1the improved fball-pro.-

peiling device as embodied in a preferred form of construction, by Way of example, it will be understood 4that it may be modiiied in Various partioulars without departing from the spirit of the invention. Consequently, I do not desire to be limited by the foregoing specication, but de sire to be afforded the full scope of the appended claim.

I claim as my invention:

A propelling device for use with a game structure having a Wall provided with an aperture, comprising: a bearing member adapted to be secured against the outer side of said Wall and provided With a bore, a counterbore and a tubular extension adapted to pass through said aperture into the game structure, said counterbore being of the same diameter as the inner diameter of said extension; a tubular plunger adapted to slide in said extension and said counterbore and having a screw-threaded connector element at its outer end; a striker head screwed onto said connector element; a stem connected to said connector element and extending through said plunger and said bore; a knob attached to the other end of said stem by Which said plunger can be drawn into said bearing member; and a spring surrounding said stem between said connector element and the inner end of said counterbore, said spring being compressed when said plunger is drawn into said bearing member by said stem and adapted to propel said plunger in the opposite direction when said stem is released, said head being engageable with the inner end of said tubular extension when said plunger is slid into said extension so as to limit the extent of inward sliding movement of said plunger .to that necessary to effect only partial compression of said spring.

GEORGE A. HATHERELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 454,603 Phillips June 23, 1891 937,078 Laudermilch Oct. 19, 1.909

1,571,643 Renick Feb. 2, 1926 2,062,204 Blackmore Nov. 24, 1936 2,139,783 VanTuyle Dec. 13, 1938 2,140,875 Kahler Dec. 20, 1938 

